Google is helping to diagnosis and prevention

Google, Microsoft and Yahoo are the U.S. sites that have the most users abroad, and this has not always been the case.
According to ComScore Networks, the three-quarters of their traffic comes from abroad. Yet ten years ago, 65% of traffic was internal, this share fell to 25%.
Regarding Google, the traffic outside the USA is 90%.

Google used by doctors for diagnosis difficult

Australian researchers from Princess Alexandra Hospital in Brisbane have found that when doctors failed to diagnose a rare disease, they use Google, so they have conducted a study to measure the value of the contribution of search engine.
By choosing some names of diseases recognized as being difficult to diagnose, they searched on Google with the names of diseases and found that it provided a list of corresponding symptoms, so a correct diagnosis in 58% of cases.
It is also happened, a doctor giving as search key symptoms of a rare disease, found at the top of the results the name of the disease itself.

Google also reveals epidemics

Google revealed recently (November 2008) that the research done on the engine, associated with a statistical map, helps reveal the spread of epidemics (including influenza) 15 days earlier than can be done with the conventional warning administrative systems!
Indeed people when they are affected exhibit the appearance of disease by research on the symptoms and remedies.
Google provides tools to determine the frequency of searches on keywords, and their evolution over time.

What Google says:

We found a close relationship between research on the subjects on influenza and the number of people presenting symptoms. Of course every person who seeks "flu" is not necessarily affected, but a trend emerges when all the research for a state, region, are put together. We compared our numbers avonc queries data from a monitoring center operated by the CDC (Centers for Disease Control and Prevention) American and discovered that some search queries became popular when the flu season arrives. By deducting the frequency with which these are search queries, we can estimate how the flu is spreading in every region of the USA.